Abstract: Technical solutions are described for current sensor fault mitigation for systems with permanent magnet DC drives. An example power steering system includes a brush motor, and a motor control system that generates an amount of torque using the brush motor, the amount of torque corresponding to a torque command. The motor control system includes a current sensor fault detector that detects a current sensor fault associated with a current sensor used to measure a current across the brush motor. The motor control system further includes a velocity observer that computes an estimated motor velocity in response to the current sensor fault. The motor control system further includes a feedforward controller that generates a current command for generating the amount of torque using the brush motor, the current command generated using the estimated motor velocity.

Abstract: Technical solutions are described for providing driver warning using steering systems. An example steering system includes a motor control system that sends a command to a motor. The steering system further includes a fault monitoring system that sets a fault indication flag by monitoring one or more components of the steering system. The steering system further includes a driver warning feedback system that generates a warning injection signal based on and in response to the fault indication flag being set. Further, the motor control system generates a driver feedback by modifying the command to the motor using the warning injection signal, and sending the modified command to the motor.

Abstract: One or more embodiments are described for preventing controller windup in a motion control system. An example system includes a regulator that receives an input command to adjust a motion control variable of a mechanical system that includes a motor, the regulator configured to generate a first torque command based on the input command and an output torque from the motor. The system further includes a motor control module that receives the first torque command to generate an input torque command that is sent to the motor. The system further includes an anti-windup module that is configured to generate an anti-windup command based on the first torque command and the output torque, the anti-windup command being added to the input command that is sent to the regulator.

Abstract: Technical solutions are described for generating an output torque from a multi-winding PMDC motor. An example method includes generating, by a current controller, a first voltage command for a first winding set from a plurality of winding sets of the PMDC motor, the first winding set generates a first current in response to the first voltage command. The method further includes generating, by the current controller, a second voltage command for the second winding set from the winding sets of the PMDC motor, the second winding set generates a second current in response to the second voltage command. The method further includes generating, by the PMDC motor, the output torque based on the first current and the second current.

Abstract: According to one or more embodiments, an example system includes a motor, and a motor control system that includes a low side current measurement subsystem. The system further includes a processor that switches the motor control system to use feedforward current control in response to detecting a current measurement failure in the low side current measurement subsystem. The processor further identifies a first phase that has a failed current measurement. The processor also computes a current measurement for the first phase, which has the current measurement failure. The processor further uses the computed current measurement to compute a parameter estimate.

Abstract: A motor control system is configured to: determine a current supply limit for an electric motor; receive a current supply of the electric motor; identify one or more motor commands; adjust the one or more motor commands in response to a determination that the current supply is greater than the current supply limit; and selectively control the electric motor using the adjusted one or more motor commands.

Abstract: According to one or more embodiments of the present invention a steer by wire steering system includes a deviation detection unit configured to determine a deviation signal that is indicative of a disturbance in one or more components coupled to a rack. The steer by wire steering system further includes a handwheel notification module configured to generate a modification signal based on the deviation signal, in response to the deviation signal being detected for at least a predetermined duration. The steer by wire steering system further includes a handwheel control module that generates an input command corresponding to a reference torque generated by a road wheel actuator, a feedback torque for a driver is generated based on the input command. The handwheel control module further modifies the input command using the modification signal, the modification providing a notification corresponding to the disturbance to the driver.

Abstract: Technical solutions are described for inverter commutation techniques for five-phase synchronous motor drives. An example method for five-phase motor control of a five-phase motor in a steering system includes receiving, by a processing device, a commanded modulation index mi, a phase advance angle ?, and a measured position ?m. The method further includes generating, by the processing device, five duty cycles for each phase of the five-phase motor based at least in part on the commanded modulation index mi, the phase advance angle ?, and the measured position ?m. Each of the duty cycles includes a fundamental component and an injected harmonic component. The method further includes performing, by the processing device, a pulse width modulation technique on each of the five duty cycles to generate on-times for a plurality of switches in phase legs of an inverter.

Abstract: Technical solutions are described for a motor control system to control a permanent magnet DC (PMDC) machine. An example motor control system includes one or more sensors for measuring an output current of the PMDC machine. The motor control system further includes a current regulator that generates a voltage command corresponding to an input current command for generating an amount of torque using the PMDC machine. The current regulator includes a current command compensator that generates a first voltage command based on the input current command received by the current regulator. The current regulator further includes a feedback compensator that generates a second voltage command based on the output current measured by the one or more sensors. The current regulator also includes an adder configured that generates the voltage command by adding the first voltage command and the second voltage command.

Abstract: According to one or more embodiments, an example system includes a motor, and a motor control system that includes a low side current measurement subsystem. The system further includes a processor that switches the motor control system to use feedforward current control in response to detecting a current measurement failure in the low side current measurement subsystem. The processor further identifies a first phase that has a failed current measurement. The processor also computes a current measurement for the first phase, which has the current measurement failure. The processor further uses the computed current measurement to compute a parameter estimate.

Abstract: A system includes a first module that: receives the output current from the electric motor as a feedback, the output current including a direct axis component and a quadrature axis component; and generates a first voltage command based on a virtual resistance value, the feedback, and a targeted frequency characteristic of the motor control system. The system includes: a second module that: receives a difference between the feedback and a commanded current; and generates a second voltage command based on an estimated inductance value, an estimated resistance value of an electric motor, the virtual resistance value, a targeted frequency response characteristic of the motor control system, and the response of the d-axis component of the output current being decoupled from the response of the q-axis component. The system includes an addition module that generates an input voltage command for the electric motor by adding the first and second voltage commands.

Abstract: Technical solutions are described for attenuating dither noise in a steering system. An example method includes computing a torque command based on an input torque, and generating a current command corresponding to the torque command. Further, the method includes determining an adjustment parameter based on a plurality of steering system signals. Further, the method includes reducing dither noise of the steering system by dynamically modifying a controller parameter value using the adjustment parameter. Further, the method includes generating a voltage command using the current command and the modified controller parameter value, the voltage command used to generate torque by a motor.

Abstract: Technical solutions are described for a control system that includes a current command module configured to receive a torque command and output a current command for controlling a direct current (DC) motor, and a regenerative current limiting module configured to receive a regenerative current limit as an input and actively compute a motor current limit based on the regenerative current limit, the regenerative current limiting module configured to limit the current command based on the motor current limit.

Abstract: Technical solutions are described for inverter commutation techniques for five-phase synchronous motor drives. An example method for five-phase motor control of a five-phase motor in a steering system includes receiving, by a processing device, a commanded modulation index mi, a phase advance angle ?, and a measured position ?m. The method further includes generating, by the processing device, five duty cycles for each phase of the five-phase motor based at least in part on the commanded modulation index mi, the phase advance angle ?, and the measured position ?m. Each of the duty cycles includes a fundamental component and an injected harmonic component. The method further includes performing, by the processing device, a pulse width modulation technique on each of the five duty cycles to generate on-times for a plurality of switches in phase legs of an inverter.

Abstract: According to one or more embodiments of the technical solutions described herein, an example method includes determining an input voltage (Vinv) of an inverter in a power circuit. The method further includes measuring an input current (Ii) of the inverter. The method further includes estimating a power supply current from a power supply of the power circuit based on the input voltage and the input current using a state observer and a plant model of the power circuit, the power supply current estimated at a non-steady state. The method further includes performing an active power management of a motor that receives electric power via the inverter.

Abstract: Technical solutions are described for generating an output torque from a multi-winding PMDC motor. An example method includes generating, by a current controller, a first voltage command for a first winding set from a plurality of winding sets of the PMDC motor, the first winding set generates a first current in response to the first voltage command. The method further includes generating, by the current controller, a second voltage command for the second winding set from the winding sets of the PMDC motor, the second winding set generates a second current in response to the second voltage command. The method further includes generating, by the PMDC motor, the output torque based on the first current and the second current.

Abstract: Improvements to a power input circuit of an electric motor drive system are provided. The power input circuit is provided between a power source (e.g., battery), and a load (e.g., an inverter and a motor in the electric motor drive system). The power input circuit can comprise controllable switches for reverse polarity protection and isolation of the inverter under supply short circuit condition. In addition, an improvement to a power input circuit can comprise connection of a power supply (e.g., voltage regulator) to the external power source input side of a reverse polarity protection circuit in the power input circuit to mitigate against microcontroller restart from post-failure shutdown condition. Connection of a low-power diode in series with the voltage regulator also provides for reverse polarity protection.

Abstract: According to one or more embodiments of the technical solutions described herein, a method for generating torque in a steering system includes computing, by a controller, a lateral velocity of a vehicle using a vehicle model that uses a vehicle velocity, a surface friction estimate, a tire-angle, and at least one of a measured yaw rate from a yaw rate sensor and a lateral acceleration. The method further includes generating, by the controller, a torque command for providing assist torque to a driver, the torque command is based on the lateral velocity that is computed. The method further includes providing, by a motor, the assist torque, which is an amount of torque corresponding to the torque command.

Abstract: Technical solutions are described for applying machine current limiting in permanent magnet synchronous motors. An example system includes a PMSM and a motor control system. The motor control system is configured to receive a torque command and determine whether the torque command can be satisfied based on a given voltage and a given maximum motor current limit. The motor control system is further configured to, responsive to determining that the torque command can be satisfied, determine a minimum current that satisfies the torque command. The motor control system is further configured to send the minimum current as a minimum current command to the PMSM.

Abstract: An embodiment of a control system includes a current command module configured to receive a torque command and output a current command for controlling a direct current (DC) motor, and a current capability limiting module configured to receive the current command and a current limit indicating a maximum motor current, limit the current command based on the current limit, and actively further limit the current command based on a capability limit value.